#include <iostream>
#include <cstdio>

// 打开命名空间
using namespace std;

namespace mytest {
	int num;
}

int main(void)
{
	int n;

	mytest::num = 100;

	cin >> n;

	cout << "n的值是" << n << std::endl;

	cout << "hello world" << std::endl;
	printf("good morning\n");

	return 0;
}

